Passing the Torch
Yu, wearing his Penn State tie, during the interview for this article.
SPIE Fellow Francis T.S. Yu, recipient of the 2004 SPIE Dennis Gabor Award, credits his success in the field of optics to all of his students, past and present.
My students are not only my faithful collaborators but also my friends," says Yu. "Although I have guided them to become independent researchers, at the same time I have learned from them. Without their efforts and dedication, we would not be able to accomplish the tasks we have."
Yu grew up in Manila, Philippines. During his high school years Yu explains he was a relatively poor student but a successful soccer player. By the time he entered college, things had changed. He was an excellent student and a very good soccer player, and, in 1956, he graduated with highest honors from the Mapúa Institute of Technology in Manila.
Yu moved to the United States and entered graduate school at the University of Michigan (U of M; Ann Arbor, MI) in 1956 where he earned his MS in 1958 and his PhD in 1964, both in electrical engineering. It was during this time that transmission-type holography (later known as the Leith hologram) was discovered at the university.
"Since holography and optical information processing share a profound relationship with the theory of information, it was a defining moment that motivated me to get involved," says Yu. And thus a career was born.
In the 1960s, optics research work was carried out at the Willow Run Laboratory at the U of M. As a non-U.S. student without proper clearance, Yu was not able to work there at the time. Nevertheless, things worked out when, a few years later, he was hired for a summer job by the former director of Willow Run. Since then Yu has been heavily involved in optics and photonics.
During his early career, Yu was one of the original inventors of the white light one-step hologram in partially coherent signal processing. He improved Stephen Benton's two-step rainbow hologram to one-step, and a method Yu developed to process and store color images using coded black and white film is still in use today.
In the late 1980s and early '90s Yu introduced various spatial light modulators to real-time optical correlators. He was an advocate of hybrid optical computer signal processing. Yu was also one of the pioneers of optical neural networks, having invented the neural network model of the InterPattern Association. This model is still used by many groups around the world. His most recent work has concentrated on photonic and optical classes.
In addition to his research and consulting work, Yu's passion centers around teaching. Yu taught at the U of M for a few years after he graduated from its electrical engineering program. In 1966 Yu moved to Wayne State University (Detroit, MI) where he was appointed assistant professor, then associate professor, and, eventually, full professor. He stayed at Wayne State until 1980 when he moved to The Pennsylvania State University (Penn State; University Park, PA). He has been the director of the Center for Electro-Optics Research at Penn State since 1985.
Yu with a group of his former PhD students who returned to Penn State to honor him before his retirement.
"The highlight of my career to date was moving from Wayne State to Penn State," says Yu. "The research environment and academic atmosphere is outstanding."
Over the course of his career, he has taught electromagnetics, communication and information theory, circuit syntheses, and coherent optics.
Yu has developed two senior-level graduate classes and two instructional optics/photonics laboratories at Penn State. He has guided more than 45 PhD students over his illustrious career, has high expectations for all of his pupils, and tries very hard to impart student independence.
"I have learned a lot from my students. It seems like I am their advisor, but at the same time they are also my teachers. I try to let them know that I am expecting them to eventually accomplish more than I have, otherwise I would be very disappointed," Yu says.
"I always enjoy working with the foreign students," he says. "Our research in optics and photonics has spread to the major continents around the world. One of the most rewarding experiences is visiting other countries and witnessing our work being carried over into their research programs."
Francis T.S. Yu and his wife, Lucy.
Yu says optics and photonics will certainly play a more active and profound role in our daily lives. This role should be credited to the discovery and development of new coherent light sources and photonic devices.
"A picture is worth more than a thousand words," says Yu. "Optics/photonics can convey and process information more rapidly than their electrical counterparts. I would anticipate the application of optics and photonics to new technology will become more and more a part of everyone's lives."
Yu has published 10 books over his lengthy career, many of which have been translated into different languages, and has edited three monographs. He has published more than 300 papers and has lectured, given seminars, and been invited to speak more than 290 times at prestigious universities and research institutions worldwide. Yu also holds three patents.
As well as being an SPIE Fellow, Yu is a fellow of the Optical Society of America and the Institute of Electrical and Electronics Engineers (IEEE). He received the Presidential Gold Medal Award from the Mapúa Institute of Technology in 1956, the Faculty Scholar Medal for Outstanding Achievement in Physical Sciences and Engineering from Penn State in 1983, the Outstanding Researcher Award from Penn State in 1984, the Penn State Engineering Society Premier Research Award in 1993, and the Donald B. Fink Prize from IEEE in 1998, just to name a few of his accolades. He was also named the Evan Pugh Professor of Engineering, the highest rank conferred at Penn State, in 1985.
Yu will retire soon but will continue to give lectures and seminars to inspire new students to enter the field of optics and photonics. He will also continue to conduct research.
"Humans are mortal, and that includes scientists, engineers, and teachers," says Yu. "My basic philosophy is that a person who knows how to advance should also know how to retreat, otherwise it causes an impediment for newcomers to grow."
A quote featured on Yu's web site and prominently in his life and research is: "One cannot get something from nothing, even by simple observation (i.e., optics). There is always a price to pay (e.g., entropy)." Yu says, "The question is thatcan one afford it?"